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Warlic
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Imagine the flagpole and ball with mass m fall together. Can I here use the formula mg*l*sin(theta)=(1/2)*mv^2
If I can, in what direction will the velocity vector be - is it going to be tangential to the flagpole?
"the diameter of the ball is much smaller than the length of the pole."stockzahn said:You can use the formula, if
1) the mass of the pole can be neglected and
2) the diameter of the ball is much smaller than the length of the pole.
The velocity vector would be perpendicular to the pole (but I think that's what you ment).
Alright, thank you, I think I get the idea nowstockzahn said:For the same reason as discussed yesterday. This formula couldn't be applied for the pole because each slice dm moves with a different velocity depending on the position. If the diameter of the ball would have a similar value as the length of the stick, then you would have to take the different slices of the ball into account. If the stick is much longr, than you can consider all slices of the ball moving with the same velocity.
It tells me there is zero potential energy at that point, everything is turned into kinetic energy?Chestermiller said:Your equation is incorrect. What does it tell you when theta is zero? Try again.
Also, what idiot made up this problem. The US flag should never be shown disrespectfully falling down!
Chet
According to your equation, the velocity is zero when theta is equal to zero.Warlic said:It tells me there is zero potential energy at that point, everything is turned into kinetic energy?
The formula for calculating kinetic energy is: KE = 1/2 * m * v^2. Where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object.
Kinetic energy is the energy an object possesses due to its motion, while potential energy is the energy stored in an object due to its position or state. Kinetic energy is related to an object's movement, while potential energy is related to its position or condition.
Yes, the formula for kinetic energy can be applied to all objects, regardless of their shape, size, or composition. However, it is important to note that the formula assumes the object is moving in a straight line at a constant speed.
Kinetic energy is closely related to work, as work is what is required to change an object's kinetic energy. According to the work-energy theorem, the work done on an object is equal to the change in its kinetic energy.
The units of kinetic energy are Joules (J) in the International System of Units (SI). In other systems, such as the British Gravitational System, the unit for kinetic energy is the foot-pound (ft-lb).